The Chosen One can talk to Phyllis about the lack of children in Vault City. With a Perception of 6 and a Doctor skill of 75%, they can convince her to talk to Dr. Troy about the potential of sterility in the population.

The Chosen One can donate sperm to help improve the genetic diversity of Vault City, after following the dialogue line about there being no children whatsoever in the town. (It is also possible to lampshade that there are no children because someone might be playing the European version of Fallout 2). If asked for a magazine aid, a Cat's Paw will be given.

The experience reward depends on Intelligence: 4 will net 50 XP, at least 5 will give 250 while 7 and above will give the full 500 XP.